Rice

From BioenergyWiki

Rice (Oryza sativa), is a cultivated grain in the grass family. More than one-half of the world's population relies on rice as their staple source of food energy. [1] Rice plays a critical role in ensuring food security in developing nations in Asia and Africa, but increasing population densities and limited land and water resources assert pressure on fragile natural environments. The Food and Agriculture Organization advocates measures that intensify rice yields on existing cultivated land, if future global demand is to be met in an environmentally sustainable manner. [2] Research is currently being done into the potential for non-consumable rice straw (which is left over after the fruiting stalks are harvested) to be converted to bioethanol. This resource could provide an important source of bioenergy.

Newly harvested flood rice with grains still attached to the stalk. (Madagascar)

Environmental Sustainability

Greenhouse Gases

Because of the semiaquatic nature of rice, global rice cultivation is responsible for significant emissions of the greenhouse gas, methane. According to the International Food Policy Research Institute, "recent assessments of methane emissions from irrigated rice cultivation estimate global emissions for the year 2000 at a level corresponding to 625 million metric tons (mt) of carbon dioxide equivalent." [4] (PDF)

Biodiversity

Pollution

Land Degradation

Social Sustainability

Technology/Science

The System of Rice Intensification is an improved yield rice farming method originally developed in Madagascar that modifies fundamental growing conditions such as increasing root zone area, controlling irrigation, and regularly eliminating competition, to stimulate rice plant development and radically increase yields. This technique is promoted in developing countries in Africa and Asia as method for ensuring food security and reducing the environmental impacts of agriculture in areas of high density rice production.

"Researchers at Purdue University propose creating mobile processing plants that would roam the Midwest to produce biofuels using a technique called fast-hydropyrolysis-hydrodeoxygenation, the West Lafayette, Ind., university said this week in a release."

"WorldStoves, a company that makes a number of pyrolitic stoves, has partnered with the NGO International Lifeline Fund and a private Haitian company to bring its 'Lucia' stove designs to Haiti. In Haiti, the use of wood for charcoal for home cooking needs is widespread, which has led to a continuing cycle of deforestation and soil [degradation]."

"What makes the Lucia stove so magic is that a Haitian woman or man could cook for a five-person family using just about 300 grams of twigs, groundnut shells, rice husk or dung."

"[If] biochar is included in the UN's Certified Emission Reductions (CER) and Clean Development Mechanism (CDM) schemes, creating it in cookstoves and sequestering it in soil could help Haiti economically as well."[8]

"To break the reliance on charcoal, villagers and refugees are being urged to use presses, paid for by the Rwandan wildlife service, that turn...leaf mulch, rice husks and other organic waste into fuel briquettes".[9]

"[L]and use is also one of the biggest contributors to global warming....The vast majority comes from deforestation, methane emissions from animals and rice fields, and nitrous oxide emissions from heavily fertilized fields. Yet, for some reason, agriculture has been largely able to avoid the attention of emissions reductions policies."[10]

Rice straw has a soft spot for bioethanol, 2 June 2009 by Checkbiotech: "Production of biofuels from inedible parts such as rice straw is so far not economically viable", however further advances in research could allow Japan to produce "2.6 billion liters of bioethanol per year from the accumulating rice straw." [11]

Japan's Ministry of Agriculture has proposed allocating 1.2 billion yen (US$11.2 million) in the coming year for private projects including for development of cellulosic ethanol technology, in addition to support for "consortiums comprising farmers, engineers and regional governments to produce ethanol from non-food soft plant parts such as rice stems and use it locally."